package com.example.administrator.mvpframe.common.widget;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Typeface;
import android.os.Build;
import android.os.Parcel;
import android.os.Parcelable;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.util.TypedValue;
import android.view.Gravity;
import android.view.View;
import android.view.ViewTreeObserver;
import android.widget.HorizontalScrollView;
import android.widget.ImageButton;
import android.widget.LinearLayout;
import android.widget.TextView;

import com.example.administrator.mvpframe.R;

import java.util.Locale;

public class PagerSlidingTabStrip extends HorizontalScrollView {

    public interface IconTabProvider {

        public int getPageIconResId(int position);
    }

    private static final int[] ATTRS = new int[]{
            android.R.attr.textSize,
            android.R.attr.textColor
    };
    private LinearLayout.LayoutParams defaultTabLayoutParams;

    private LinearLayout.LayoutParams expandedTabLayoutParams;

    private final PageListener pageListener = new PageListener ();

    public ViewPager.OnPageChangeListener delegatePageListener;

    private LinearLayout tabsContainer;

    private ViewPager pager;

    private int tabCount;

    private int currentPosition = 0;

    private float currentPositionOffset = 0f;

    private Paint rectPaint;

    private Paint dividerPaint;

    private int indicatorColor = 0xFF666666;

    private int underlineColor = 0x1A000000;

    private int dividerColor = 0x1A000000;

    private boolean shouldExpand = false;

    private boolean textAllCaps = true;

    private int scrollOffset = 52;

    private int indicatorHeight = 8;

    private int underlineHeight = 2;

    private int dividerPadding = 12;

    private int tabPadding = 24;

    private int dividerWidth = 1;

    private int tabTextSize = 12;

    private int tabTextColor = 0xFF666666;

    private int tabSelectedColor = 0xFF36C9FB;

    private Typeface tabTypeface = null;

    private int tabTypefaceStyle = Typeface.BOLD;

    private int lastScrollX = 0;

    private int tabBackgroundResId = R.drawable.background_tab;

    private Locale locale;

    public PagerSlidingTabStrip(Context context) {
        this (context, null);
    }

    public PagerSlidingTabStrip(Context context, AttributeSet attrs) {
        this (context, attrs, 0);
    }

    public PagerSlidingTabStrip(Context context, AttributeSet attrs, int defStyle) {
        super (context, attrs, defStyle);

        setFillViewport (true);
        setWillNotDraw (false);

        tabsContainer = new LinearLayout (context);
        tabsContainer.setOrientation (LinearLayout.HORIZONTAL);
        tabsContainer.setLayoutParams (new LayoutParams (LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
        addView (tabsContainer);

        DisplayMetrics dm = getResources ().getDisplayMetrics ();

        scrollOffset = (int) TypedValue.applyDimension (TypedValue.COMPLEX_UNIT_DIP, scrollOffset, dm);
        indicatorHeight = (int) TypedValue.applyDimension (TypedValue.COMPLEX_UNIT_DIP, indicatorHeight, dm);
        underlineHeight = (int) TypedValue.applyDimension (TypedValue.COMPLEX_UNIT_DIP, underlineHeight, dm);
        dividerPadding = (int) TypedValue.applyDimension (TypedValue.COMPLEX_UNIT_DIP, dividerPadding, dm);
        tabPadding = (int) TypedValue.applyDimension (TypedValue.COMPLEX_UNIT_DIP, tabPadding, dm);
        dividerWidth = (int) TypedValue.applyDimension (TypedValue.COMPLEX_UNIT_DIP, dividerWidth, dm);
        tabTextSize = (int) TypedValue.applyDimension (TypedValue.COMPLEX_UNIT_SP, tabTextSize, dm);

        // get system attrs (android:textSize and android:textColor)

        TypedArray a = context.obtainStyledAttributes (attrs, ATTRS);

        tabTextSize = a.getDimensionPixelSize (0, tabTextSize);
        tabTextColor = a.getColor (1, tabTextColor);

        a.recycle ();

        // get custom attrs

        a = context.obtainStyledAttributes (attrs, R.styleable.PagerSlidingTabStrip);

        indicatorColor = a.getColor (R.styleable.PagerSlidingTabStrip_pstsIndicatorColor, indicatorColor);
        underlineColor = a.getColor (R.styleable.PagerSlidingTabStrip_pstsUnderlineColor, underlineColor);
        dividerColor = a.getColor (R.styleable.PagerSlidingTabStrip_pstsDividerColor, dividerColor);
        indicatorHeight = a.getDimensionPixelSize (R.styleable.PagerSlidingTabStrip_pstsIndicatorHeight, indicatorHeight);
        underlineHeight = a.getDimensionPixelSize (R.styleable.PagerSlidingTabStrip_pstsUnderlineHeight, underlineHeight);
        dividerPadding = a.getDimensionPixelSize (R.styleable.PagerSlidingTabStrip_pstsDividerPadding, dividerPadding);
        tabPadding = a.getDimensionPixelSize (R.styleable.PagerSlidingTabStrip_pstsTabPaddingLeftRight, tabPadding);
        tabBackgroundResId = a.getResourceId (R.styleable.PagerSlidingTabStrip_pstsTabBackground, tabBackgroundResId);
        shouldExpand = a.getBoolean (R.styleable.PagerSlidingTabStrip_pstsShouldExpand, shouldExpand);
        scrollOffset = a.getDimensionPixelSize (R.styleable.PagerSlidingTabStrip_pstsScrollOffset, scrollOffset);
        textAllCaps = a.getBoolean (R.styleable.PagerSlidingTabStrip_pstsTextAllCaps, textAllCaps);

        a.recycle ();

        rectPaint = new Paint ();
        rectPaint.setAntiAlias (true);
        rectPaint.setStyle (Paint.Style.FILL);

        dividerPaint = new Paint ();
        dividerPaint.setAntiAlias (true);
        dividerPaint.setStrokeWidth (dividerWidth);

        defaultTabLayoutParams = new LinearLayout.LayoutParams (LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT);
        expandedTabLayoutParams = new LinearLayout.LayoutParams (0, LayoutParams.MATCH_PARENT, 1.0f);

        if (locale == null) {
            locale = getResources ().getConfiguration ().locale;
        }
    }

    public void setViewPager(ViewPager pager) {
        this.pager = pager;

        if (pager.getAdapter () == null) {
            throw new IllegalStateException ("ViewPager does not have adapter instance.");
        }

        pager.setOnPageChangeListener (pageListener);

        notifyDataSetChanged ();
    }

    public void setOnPageChangeListener(ViewPager.OnPageChangeListener listener) {
        this.delegatePageListener = listener;
    }

    public void notifyDataSetChanged() {

        tabsContainer.removeAllViews ();

        tabCount = pager.getAdapter ().getCount ();

        for (int i = 0; i < tabCount; i++) {

            if (pager.getAdapter () instanceof IconTabProvider) {
                addIconTab (i, ((IconTabProvider) pager.getAdapter ()).getPageIconResId (i));
            } else {
                addTextTab (i, pager.getAdapter ().getPageTitle (i).toString ());
            }

        }

        updateTabStyles ();

        getViewTreeObserver ().addOnGlobalLayoutListener (new ViewTreeObserver.OnGlobalLayoutListener () {

            @SuppressWarnings("deprecation")
            @SuppressLint("NewApi")
            @Override
            public void onGlobalLayout() {

                if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
                    getViewTreeObserver ().removeGlobalOnLayoutListener (this);
                } else {
                    getViewTreeObserver ().removeOnGlobalLayoutListener (this);
                }

                currentPosition = pager.getCurrentItem ();
                scrollToChild (currentPosition, 0);

                if(delegatePageListener != null){
                    delegatePageListener.onPageSelected(currentPosition);
                }
            }
        });
    }

    private void addTextTab(final int position, String title) {

        TextView tab = new TextView (getContext ());
        tab.setText (title);
        tab.setGravity (Gravity.CENTER);
        tab.setSingleLine ();

        addTab (position, tab);
    }

    private void addIconTab(final int position, int resId) {

        ImageButton tab = new ImageButton (getContext ());
        tab.setImageResource (resId);

        addTab (position, tab);

    }

    private void addTab(final int position, View tab) {
        tab.setFocusable (true);
        tab.setOnClickListener (new OnClickListener () {

            @Override
            public void onClick(View v) {
                pager.setCurrentItem (position);
            }
        });

        tab.setPadding (tabPadding, 0, tabPadding, 0);
        tabsContainer.addView (tab, position, shouldExpand ? expandedTabLayoutParams : defaultTabLayoutParams);
    }

    private void updateTabStyles() {

        for (int i = 0; i < tabCount; i++) {

            View v = tabsContainer.getChildAt (i);

            v.setBackgroundResource (tabBackgroundResId);

            if (v instanceof TextView) {

                TextView tab = (TextView) v;
                tab.setTextSize (TypedValue.COMPLEX_UNIT_PX, tabTextSize);
                if (pager.getCurrentItem () == i) {
                    tab.setTextColor (tabSelectedColor);
                } else {
                    tab.setTextColor (tabTextColor);
                }
                // setAllCaps() is only available from API 14, so the upper case is made manually if we are on a
                // pre-ICS-build
                if (textAllCaps) {
                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
                        tab.setAllCaps (true);
                    } else {
                        tab.setText (tab.getText ().toString ().toUpperCase (locale));
                    }
                }
            }
        }

    }

    private void scrollToChild(int position, int offset) {

        if (tabCount == 0) {
            return;
        }

        int newScrollX = tabsContainer.getChildAt (position).getLeft () + offset;

        if (position > 0 || offset > 0) {
            newScrollX -= scrollOffset;
        }

        if (newScrollX != lastScrollX) {
            lastScrollX = newScrollX;
            scrollTo (newScrollX, 0);
        }

    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw (canvas);

        if (isInEditMode () || tabCount == 0) {
            return;
        }

        final int height = getHeight ();


        rectPaint.setColor (indicatorColor);

        View currentTab = tabsContainer.getChildAt (currentPosition);
        float lineLeft = currentTab.getLeft ();
        float lineRight = currentTab.getRight ();

        if (currentPositionOffset > 0f && currentPosition < tabCount - 1) {

            View nextTab = tabsContainer.getChildAt (currentPosition + 1);
            final float nextTabLeft = nextTab.getLeft ();
            final float nextTabRight = nextTab.getRight ();

            lineLeft = (currentPositionOffset * nextTabLeft + (1f - currentPositionOffset) * lineLeft);
            lineRight = (currentPositionOffset * nextTabRight + (1f - currentPositionOffset) * lineRight);
        }

        canvas.drawRect (lineLeft, height - indicatorHeight, lineRight, height, rectPaint);


        rectPaint.setColor (underlineColor);
        canvas.drawRect (0, height - underlineHeight, tabsContainer.getWidth (), height, rectPaint);


        dividerPaint.setColor (dividerColor);
        for (int i = 0; i < tabCount - 1; i++) {
            View tab = tabsContainer.getChildAt (i);
            canvas.drawLine (tab.getRight (), dividerPadding, tab.getRight (), height - dividerPadding, dividerPaint);
        }
    }

    private class PageListener implements ViewPager.OnPageChangeListener {

        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

            currentPosition = position;
            currentPositionOffset = positionOffset;

            scrollToChild (position, (int) (positionOffset * tabsContainer.getChildAt (position).getWidth ()));

            invalidate ();

            if (delegatePageListener != null) {
                delegatePageListener.onPageScrolled (position, positionOffset, positionOffsetPixels);
            }
        }

        @Override
        public void onPageScrollStateChanged(int state) {
            if (state == ViewPager.SCROLL_STATE_IDLE) {
                scrollToChild (pager.getCurrentItem (), 0);
            }

            if (delegatePageListener != null) {
                delegatePageListener.onPageScrollStateChanged (state);
            }
        }

        @Override
        public void onPageSelected(int position) {
            if (delegatePageListener != null) {
                delegatePageListener.onPageSelected (position);
            }
            updateTabStyles ();
        }

    }

    public void setIndicatorColor(int indicatorColor) {
        this.indicatorColor = indicatorColor;
        invalidate ();
    }

    public void setIndicatorColorResource(int resId) {
        this.indicatorColor = getResources ().getColor (resId);
        invalidate ();
    }

    public int getIndicatorColor() {
        return this.indicatorColor;
    }

    public void setIndicatorHeight(int indicatorLineHeightPx) {
        this.indicatorHeight = indicatorLineHeightPx;
        invalidate ();
    }

    public int getIndicatorHeight() {
        return indicatorHeight;
    }

    public void setUnderlineColor(int underlineColor) {
        this.underlineColor = underlineColor;
        invalidate ();
    }

    public void setUnderlineColorResource(int resId) {
        this.underlineColor = getResources ().getColor (resId);
        invalidate ();
    }

    public int getUnderlineColor() {
        return underlineColor;
    }

    public void setDividerColor(int dividerColor) {
        this.dividerColor = dividerColor;
        invalidate ();
    }

    public void setDividerColorResource(int resId) {
        this.dividerColor = getResources ().getColor (resId);
        invalidate ();
    }

    public int getDividerColor() {
        return dividerColor;
    }

    public void setUnderlineHeight(int underlineHeightPx) {
        this.underlineHeight = underlineHeightPx;
        invalidate ();
    }

    public int getUnderlineHeight() {
        return underlineHeight;
    }

    public void setDividerPadding(int dividerPaddingPx) {
        this.dividerPadding = dividerPaddingPx;
        invalidate ();
    }

    public int getDividerPadding() {
        return dividerPadding;
    }

    public void setScrollOffset(int scrollOffsetPx) {
        this.scrollOffset = scrollOffsetPx;
        invalidate ();
    }

    public int getScrollOffset() {
        return scrollOffset;
    }

    public void setShouldExpand(boolean shouldExpand) {
        this.shouldExpand = shouldExpand;
        requestLayout ();
    }

    public boolean getShouldExpand() {
        return shouldExpand;
    }

    public boolean isTextAllCaps() {
        return textAllCaps;
    }

    public void setAllCaps(boolean textAllCaps) {
        this.textAllCaps = textAllCaps;
    }

    public void setTextSize(int textSizePx) {
        this.tabTextSize = textSizePx;
        updateTabStyles ();
    }

    public int getTextSize() {
        return tabTextSize;
    }

    public void setTextColor(int textColor) {
        this.tabTextColor = textColor;
        updateTabStyles ();
    }

    public void setTextColorResource(int resId) {
        this.tabTextColor = getResources ().getColor (resId);
        updateTabStyles ();
    }

    public int getTextColor() {
        return tabTextColor;
    }

    public void setTypeface(Typeface typeface, int style) {
        this.tabTypeface = typeface;
        this.tabTypefaceStyle = style;
        updateTabStyles ();
    }

    public void setTabBackground(int resId) {
        this.tabBackgroundResId = resId;
    }

    public int getTabBackground() {
        return tabBackgroundResId;
    }

    public void setTabPaddingLeftRight(int paddingPx) {
        this.tabPadding = paddingPx;
        updateTabStyles ();
    }

    public int getTabPaddingLeftRight() {
        return tabPadding;
    }

    @Override
    public void onRestoreInstanceState(Parcelable state) {
        SavedState savedState = (SavedState) state;
        super.onRestoreInstanceState (savedState.getSuperState ());
        currentPosition = savedState.currentPosition;
        requestLayout ();
    }

    @Override
    public Parcelable onSaveInstanceState() {
        Parcelable superState = super.onSaveInstanceState ();
        SavedState savedState = new SavedState (superState);
        savedState.currentPosition = currentPosition;
        return savedState;
    }

    static class SavedState extends BaseSavedState {

        int currentPosition;

        public SavedState(Parcelable superState) {
            super (superState);
        }

        private SavedState(Parcel in) {
            super (in);
            currentPosition = in.readInt ();
        }

        @Override
        public void writeToParcel(Parcel dest, int flags) {
            super.writeToParcel (dest, flags);
            dest.writeInt (currentPosition);
        }

        public static final Creator<SavedState> CREATOR = new Creator<SavedState> () {

            @Override
            public SavedState createFromParcel(Parcel in) {
                return new SavedState (in);
            }

            @Override
            public SavedState[] newArray(int size) {
                return new SavedState[size];
            }
        };
    }
}
